CN111237152A - A groove-pit combined textured axial piston pump plunger - Google Patents

Abstract

The invention relates to an axial plunger pump plunger with a groove-pit combination texture, comprising a plunger body, a plunger cavity is opened along the axis direction of the plunger body, and a right end of the plunger body has a plunger cavity. Plunger ball head, the plunger ball head is provided with a stepped hole along the axis of the plunger body, the plunger cavity is communicated with the stepped hole, and a groove is opened on the surface of the plunger body Combined texture of pits, annular groove texture I, square pit texture, annular groove texture II, the annular groove texture is on both sides of the surface of the plunger body, the square pit texture The structure is distributed alternately in two columns. The invention can improve the bearing capacity of the oil film at the friction pair of the plunger, reduce the friction force and end leakage, reduce the mechanical loss, improve the volume efficiency, and enhance the squeeze of the fluid by processing the groove-pit combined texture on the surface of the plunger. It is of great significance to guide the low-friction design of the plunger friction pair.

Description

A groove-pit combined textured axial piston pump plunger

technical field

The invention relates to the field of construction machinery, in particular to a component of an axial plunger pump, in particular to an axial plunger pump plunger with a groove-pit combined texture.

Background technique

Axial piston pump is one of the key components of hydraulic system. Due to its high working pressure, easy variable adjustment, large speed range and high efficiency, it is widely used in agricultural and forestry machinery, chemical industry, textile machinery, energy industry machinery, metallurgy Industrial machinery, building materials industry machinery, machine tool industry, as well as military, aerospace, shipbuilding and other fields, with the development of axial piston pumps in the direction of high pressure, high speed, and large flow, the problem of reducing friction and prolonging pump life is very urgent.

The plunger friction pair composed of the plunger-cylinder block is one of the three friction pairs of the axial plunger pump. During the working process, the plunger reciprocates in the cylinder body under the drive of the driving mechanism, and at the same time makes a planetary rotation around the cylinder body and the center line of the cylinder body. Due to the existence of friction, the plunger will also rotate randomly around itself in the cylinder block. In addition, due to the existence of the oil film gap, the plunger may swing slightly in the cylinder hole, and the lateral force of the swash plate acts on it. down, the plunger is always inclined in the cylinder bore. Theoretically, both ends of the plunger and the cylinder are in point contact, the lubrication situation is more complicated, the lubrication conditions are worse, and it is very easy to have solid contact.

According to statistics, the early wear of the friction pair is often one of the main reasons for the scrapping of the axial piston pump. If the design of the friction pair is unreasonable, during the high-pressure and high-speed operation of the pump, complete liquid lubrication cannot be formed between the plunger and the cylinder, and mixed friction or even dry friction may occur on the two metal walls, which may damage the parts. In order to improve the lubrication state of the plunger friction pair, reduce friction loss and leakage, and prolong the service life of the parts, it is necessary to adopt a reasonable structural design to improve the working performance of the plunger friction pair.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the tribological problem existing in the friction pair of the plunger to a certain extent. Therefore, the present invention proposes an axial piston pump with groove-dimple combined texture, which has the advantages of good lubrication effect, small mechanical loss and high volumetric efficiency under high-speed and heavy-load conditions in an oil-lubricated environment. Plunger friction pair. Based on the principle of fluid dynamic pressure, the invention processes the surface of the friction pair of the plunger of the axial piston pump into a surface with a combined texture of grooves and pits.

The present invention is achieved through the following technical solutions:

An axial plunger pump plunger with a groove-pit combination texture, comprising a plunger body, a plunger cavity is opened along the axis direction of the plunger body, and a plunger ball is arranged at the right end of the plunger body The plunger ball head is provided with a stepped hole along the axis of the plunger body, the plunger cavity is communicated with the stepped hole, the left end surface of the plunger body is an arc bottom surface, and the plunger The surface of the body is provided with parallel distributed groove-pit combined textures of different widths and depths, and the groove-pit combined texture includes annular groove texture I, square pit texture, annular groove texture Groove texture II, the annular groove texture is on both sides of the surface of the plunger body, the square pit texture is alternately distributed in two rows, and the square pit texture is opened in the annular groove texture in the middle.

The length of the unsuitable design area of the groove-pit combined texture ΔL is the stroke of the plunger when the axial piston pump is working, L _T is the length of the surface texture design area, and _LD is the left end of the groove texture. The distance from the left boundary of the region, the ratio of L _D / L _T represents the position of the groove, and its ratio ranges from 0 to 1. The annular groove IL _D /L _T is 0.2, and the annular groove IIL _D /L _T is 0.8, and the square pit texture is in the middle of the surface texture design area;

The square pit texture has the same width, different depths and is alternately distributed in two rows. The annular groove texture I, the square pit texture, the annular groove texture width is between 1.0 and 5.0 mm, and the depth is between 1.0 and 5.0 mm. Between 3 and 30 μm.

Compared with the prior art, the present invention has the following advantages:

According to the principle of fluid dynamic pressure, the invention designs the surface of the plunger as a groove-pit combined textured surface. It can be known from the knowledge of fluid mechanics that the step plane has stronger dynamic pressure capability than other shapes of planes. ; Under the action of the step effect, it can better ensure the anti-overturning moment generated by the oil film pressure field, and enhance the working reliability of the plunger. The annular groove texture on the left is used to reduce friction and prevent end leakage. Since the texture is located at L _D /L _T = 0.2, it will have an adverse effect, so a narrower and shallower annular groove texture is selected. It is two rows of alternately distributed square pit texture, its function is to improve the oil film bearing capacity and reduce friction, the right side adopts a wider and deeper annular groove texture to further reduce friction, improve oil film bearing capacity, and prevent end leak. As the groove depth increases, the fluid squeeze effect increases, and the oil film bearing capacity increases, which increases the minimum oil film thickness, reduces the possibility of solid contact, and reduces friction loss. In addition, since the groove-dimple combined texture increases the liquid resistance in the gap, the leakage of the friction pair of the plunger is reduced, and the volumetric efficiency is improved.

The invention does not add parts, only improves the lubrication performance of the friction pair of the plunger through the structural design, and has the advantages of simple structure and good economy. In addition, the structure also has the characteristics of wide applicability, and can choose groove-dimple combined texture with different distribution and size according to different working conditions, so as to ensure the excellent working performance of the plunger.

Description of drawings

1 is a partial cross-sectional view of the present invention;

Fig. 2 is the sectional view of the present invention;

Figure 3 is an assembly view of the present invention.

In the figure: 1 - plunger body; 2 - plunger cavity; 3 - plunger ball head; 4 - stepped hole; 5 - annular groove texture I; 6 - square pit texture; 7 - annular groove Ⅱ; 8-cylinder hole; 9-slipper; 10-slipper ball socket; 11-swash plate.

Detailed ways

The present invention is described in more detail below in conjunction with the accompanying drawings:

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific examples described herein are only used to explain the present invention, but not to limit the present invention.

This example provides an axial plunger pump plunger with a combined groove-dimple texture, including a plunger body 1, and the plunger body 1 is provided with a plunger cavity 2 along the axis direction, and the plunger There is a plunger ball 3 at the right end of the plunger body 1. The plunger ball 3 is provided with a stepped hole 4 along the axis of the plunger body 1. The plunger cavity 2 is communicated with the stepped hole 4. The left end surface of the plunger body is an arc-shaped bottom surface, and the surface of the plunger body 1 is provided with a groove-pit combination texture with different widths and depths in parallel distribution, that is, a groove-pit combination texture, From small to large, the annular groove texture I5, the square pit texture 6, the annular groove texture II7, the annular groove texture I5 and the annular groove texture II7 are on the surface of the plunger body 1 On both sides, the square pit textures 6 are alternately distributed in two rows, and the square pit textures 6 are opened in the middle of the annular groove texture I5 and the annular groove texture II7.

The length of the unsuitable design area of the groove-pit combined texture ΔL is the stroke of the plunger when the axial piston pump is working, L _T is the length of the surface texture design area, and _LD is the left end of the groove texture. The distance from the left boundary of the area, the ratio of L _D / L _T is used to represent the position of the groove, and its ratio range is 0 to 1. The annular groove I5L _D /L _T is 0.2, and the annular groove II7L _D /L _T is 0.8.

The square pit texture 6 has the same width, different depths and is alternately distributed in two rows. The annular groove texture I5, the square pit texture 6, and the annular groove texture II7 have a width between 1.0 and 5.0 mm. , the depth is between 3 and 30 μm.

FIG. 3 is an assembly state diagram of the present invention. During the use of the plunger, the plunger body 1 is installed in the cylinder hole 8, while the plunger ball head 3 is assembled with the sliding shoe ball socket 10, and the sliding shoe 9 is installed on the swash plate 11. During the working process, the plunger body The force of the high-pressure oil 1 is transmitted to the swash plate 11 through the sliding shoe 9. Under the reaction force of the swash plate 11 to the sliding shoe 9, the plunger body 1 reciprocates in the cylinder hole 8. Due to the surface processing of the plunger It has a groove-pit combined texture, which can improve the bearing capacity of the oil film, reduce the mechanical loss, reduce the leakage, and improve the lubrication state.

The invention can improve the bearing capacity of the oil film at the friction pair of the plunger, reduce the friction force and end leakage, reduce the mechanical loss, improve the volume efficiency, and enhance the squeeze of the fluid by processing the groove-pit combined texture on the surface of the plunger. It is of great significance to guide the low-friction design of the plunger friction pair.

The above descriptions are only good examples of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. Inside.

Claims (3)

1. The axial plunger pump plunger with the groove-pit combined type texture is characterized by comprising a plunger body (1), wherein a plunger cavity (2) is formed in the plunger body (1) along the axis direction, a plunger ball head (3) is arranged at the right end of the plunger body (1), a stepped hole (4) is formed in the plunger ball head (3) along the axis of the plunger body (1), the plunger cavity (2) is communicated with the stepped hole (4), the left end face of the plunger body is an arc-shaped bottom face, and groove-pit combined type textures which are distributed in parallel and have different widths and depths are formed in the surface of the plunger body (1); the groove-pit combined texture comprises an annular groove texture I (5), a square pit texture (6) and an annular groove texture II (7), wherein the annular groove texture I (5) and the annular groove texture II (7) are arranged on two sides of the surface of the plunger body (1), the square pit textures (6) are alternately distributed in two rows, and the square pit textures are arranged in the middle of the annular groove texture.

2. The plunger of the axial plunger pump in the groove-pit combined type structure as claimed in claim 1, wherein the length Δ L of the area which is not suitable for designing the groove-pit combined type structure is the stroke of the plunger when the axial plunger pump works, L_TDesigning the length of the area for the surface texture, L_DThe distance from the left end of the trench to the left boundary of the texture region is represented by L_D/L_TThe ratio of (A) to (B) represents the position of the groove, the ratio range is 0-1, and the annular groove I (5) L_D/L_T0.2, the annular groove II (7) L_D/L_T0.8, the square pit texture (6) is designed in the middle of the area by the surface texture.

3. The axial plunger pump plunger piston of the groove-pit combined type texture as claimed in claim 1 or 2, wherein the square pit textures (6) have the same width and different depths and are alternately distributed in two rows, the annular groove texture I (5), the square pit texture (6) and the annular groove texture II (7) have the width of 1.0-5.0 mm and the depth of 3-30 μm.

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